The Feeling Mental Factor is the Operational Companion of Consciousness

The "sensation" in the aggregate of sensation (vedanā-skandha) is a mental factor (caitasika) of the six consciousnesses, a function of the six consciousnesses. It is essentially the feeling that arises after the consciousness contacts an object. The initial phase of receiving and accepting is still a coarse aspect, merely taking in the six dusts (objects). It develops into the subtle aspect when feelings of joy, anger, sorrow, and pleasure arise. The aggregate of sensation encompasses not only the initial sensation upon contact, which is the reception and acceptance without the arising of pleasant or unpleasant feelings, but also the subsequent three types of sensation. Volition (saṃjñā) involves not only discrimination but also the function of grasping appearances; the volition of the mental consciousness corresponds to names and concepts. Volition also has coarse and subtle aspects, involving coarse discrimination and subtle discrimination along with grasping of appearances. Only after coarse and subtle discrimination occur do the coarse and subtle sensations of the six consciousnesses arise.

The seeds of sensation stored in the Tathāgatagarbha are not separate from the seeds of consciousness. When the seeds of consciousness operate, they are accompanied by the operation of the mental factor of sensation. Thus, the consciousness-mind possesses the function of sensation. It is not the case that there exists a separate seed of sensation apart from the seeds of consciousness. The five universal mental factors do not have their own seeds; they depend on the consciousness-mind to operate and are its auxiliaries. When the seeds of consciousness manifest, the five universal mental factors simultaneously accompany and operate with them; they are dependent on the consciousness-mind. Therefore, sensation does not have its own separate seeds, nor does volition. Both arise only after the seeds of the six consciousnesses manifest and the consciousness-mind begins to operate, at which point the mental factors of sensation and volition accompany its operation. All five universal mental factors function this way, and each of the eight consciousnesses possesses its own set of five universal mental factors.

In the process of discrimination by the consciousness-mind, the five universal mental factors operate repeatedly; it is not a single occurrence. Once activated, their order may interchange and invert; the sequence is not fixed. Therefore, the sensation of the six consciousnesses does not conclude after operating once or twice; it may operate countless times. The mental factors of volition and conception (cetanā) are likewise. The mental factors of attention (manasikāra) and contact (sparśa) operate relatively fewer times. The six consciousnesses can continuously attend to the six dusts and continuously contact the six dusts without fluctuation. The mental factors of sensation, volition, and conception must operate repeatedly, back and forth, before a final decision can be reached, concluding the six consciousnesses' discrimination of the six dusts. The operation of mental factors is extremely subtle; only at the stage of Buddhahood can it be fully observed.